Air filter clock



FIG. 1 is a front view of the air filter clock;

FIG. 2 is a side view of the air filter clock;

FIG. 3 is a rear view of the air filter clock;

FIG. 4 is an alternate embodiment of the front view of the air filter clock; and,

FIG. 5 is an alternate embodiment of the front view of the air filter clock.

The sides and rears of the embodiments are identical to FIGS. 2-3. 

The ornamental design for a air filter clock, as shown and described. 